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Compressible and transient flow problem
Posted Feb 27, 2013, 11:22 a.m. EST Fluid & Heat, Computational Fluid Dynamics (CFD), Microfluidics Version 4.3a 1 Reply
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Hi,
I am trying to model a tank full of air that empties with time through a thin channel (It is almost a nozzle). I used the laminar-transient formulation. I chose from the library the properties of air. I selected the compressible formulation, with a mapped mesh for fluid mechanics (20000 elements), and I chose a time step of (0,0.01,2). The program is in 1% after 1 day of computation.
Any clues of how can I improve my model to get it done faster? This is a 2D model (axisymmetric formulation) ,and it surprises me that is taking toolong. Should I use the microfluidics module for this case? Should I modify the time step? In the boundary conditions the model has an initial pressure, and the nozzle has the open boundary condition. I am looking forward to finding the time that takes to empty this tank.
Attached is my model
Thanks
I am trying to model a tank full of air that empties with time through a thin channel (It is almost a nozzle). I used the laminar-transient formulation. I chose from the library the properties of air. I selected the compressible formulation, with a mapped mesh for fluid mechanics (20000 elements), and I chose a time step of (0,0.01,2). The program is in 1% after 1 day of computation.
Any clues of how can I improve my model to get it done faster? This is a 2D model (axisymmetric formulation) ,and it surprises me that is taking toolong. Should I use the microfluidics module for this case? Should I modify the time step? In the boundary conditions the model has an initial pressure, and the nozzle has the open boundary condition. I am looking forward to finding the time that takes to empty this tank.
Attached is my model
Thanks
Attachments:
1 Reply Last Post Feb 28, 2013, 1:59 a.m. EST
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Posted:
1 decade ago
Hi
I believe its a "mesh issue", but as you have deleted the mesh structure one cannot tell how it was or should be (its enough to do a Edit Clear All Solutions - Clear all mesh File reset history) to make your file light and uploadable
I would advise to fillet slight the entry of your thin tube, now you will get a singularity on that sharp edge
--
Good luck
Ivar
I believe its a "mesh issue", but as you have deleted the mesh structure one cannot tell how it was or should be (its enough to do a Edit Clear All Solutions - Clear all mesh File reset history) to make your file light and uploadable
I would advise to fillet slight the entry of your thin tube, now you will get a singularity on that sharp edge
--
Good luck
Ivar